package com.itheima.reggie.controller;

import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

@Slf4j
@RestController
@RequestMapping("/common")
public class CommonController {
    @Value("${reggie.path}")
    private String basepath;

    @PostMapping("/upload")
    public R upload(MultipartFile file){
        log.info(file.toString());
        //file是一个临时文件,需要转存到指定位置,否则本次请求完成之后
        //临时文件会删除

        //获取原始文件名
        String originalFilename = file.getOriginalFilename();
        //获取后缀名
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));

        //使用UUID重新生成文件名,防止重复
        String fileName = UUID.randomUUID().toString() + suffix;

        //创建一个目录对象
        File dir = new File(basepath);
        //判断当前目录是否存在,不存在则创建
        if (!dir.exists()){
            dir.mkdir();
        }

        //将临时文件转存到指定位置
        try {
            file.transferTo(new File(basepath + fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }

        return R.success(fileName);
    }

    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        //获取文件对象
        File file = new File(basepath, name);
        try {
            //获取文件输入流
            FileInputStream fileInputStream = new FileInputStream(file);
            //输出流,将文件写回浏览器
            ServletOutputStream outputStream = response.getOutputStream();
            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while((len = fileInputStream.read(bytes)) != -1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }

            //关闭资源
            outputStream.close();
            fileInputStream.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}
